Method of regulating the temperature of air.



PATENTED MAR. 26, 1907. P. MANDEVILLE & W. G. WALKER. METHOD OF REGU-LATING THE TEMPERATUREIOF AIR.

APPLICATION FILED MAY 19. 1906.

2 SHEETS-SHEET 1.

' Willi 1 11111 WWI/7717717111111 5'1 N0: 848,595. PATENTED MAR. 26. 1907. P. MANDEVILLE & W. G. WALKER.

METHOD OF REGULATING THE TEMPERATURE OF AIR.

' APPLICATION PILYED MAY 19. 1906. @g 1 2 SHEETS-SHEBT 2.

[pUepf/Siqj M65565. I 4 W %ogdzw; m W

UNITED- STATES PATENT OFFICE.

PAUL MAN DEVILLE AND WILLIAM C. WALKER, OF CHICAGO, ILLINOIS; SAID MANDEVILLE ASSIGNOR TO CHARLES E. MANDEVILLE, OF CHICAGO,

ILLINOIS.

Specification of Letters Patent.

Application filed May 19,1906. Serial No. 317,824.

Patented March 2Q, 1907.

To all zohom it may concern:

Be it known that we, PAUL MANDEVILLE and WILLIAM C'. WALKER, citizens of the United States, and residin at Chicago, in the county of Cook, State 0 Illinois, have invented a certain new and Improved Method of Regulating the Temperature of Air, of which the following is a specification.

Our invention relates to the regulation of the temperature of air, particularly in con-" nection with the preservation of perishable matter, such as fruit, eggs, meat, &c.

In' transporting perishable articles grea distancesas, for .instance, bringing fruit from California to eastern marketsfor many years it was necessary to pick the fruit green, owin to the rapid ripening of the fruit in transit, with the result that there was considerable loss through the failure of the fruit to properly matureon the trees, as Well as because the fruit so ripened did not possess as good a flavor as that ripened on the trees. With the object of avoiding the objections mentioned, as Well as others incident to the older methods of handling the fruit, many-efforts have been made to improve the conditions under whichthe fruit is transported, articularly by what is called precooling o .the refrigerator-cars in which the fruit is carried.

It has been well established that if the temperature of the car-can be properly reduced immediately after the fruit has been packed in it, so that the warm air contained in-the fruit-packages is brought to a uniform temperature with the rest of the car, the'fruit will be preserved much more perfectly, as

experience has shown that practically all the deterioration of the'fruit in transit occurs during the first three days of the trip, due to the car-and promotes, decay.

Heretofore it "has been attempted to equalize the temperature'of the an in all parts of the car, including that contained in the fruit-packages, by instituting a forced circulation of cooled air through the car, the air being taken from the carthrough suitable conduits and after being conducted over refrigerating-coils bein returned to the car at the opposite end, so that the car itself formed part of a circulatory system, which included the refrigerating apparatus. In some instances, the air has been caused to pass over ice placed in suitable receptacles in the car, which have been used in lieu of the refrigerat ingcoils. This system, while an improve ment over the older practice, has not been as successful as was anticipated, for the reason that the air circulating through the car naturally takes the path of least resistance, which is in the upper part of the car and around the fruit-packages, and consequently the air that is occupying the space within the fruit-packages has' not been sufficiently affected. To meet the deficiencies of this circulatory systerm, it has been proposed to create a partial vacuum in the car at intervals, on the theory that by so doing the air in the car Will be rarefied, causing the air in the fruit-packa 'es to expand and in that Way be partly expel ed partial vacuum and maintaining a circulation through the car the 'theoryhas been that the air leaving the fruit-packages during the interval of the partial vacuum Will be brought into contact with the air in the body of the car, While the cold air entering the car at the end of the partial-vacuuminterval will be caused to mingle with the air in the fruit-packages, owing to the increase in the density of the air, caused by the restoration of circulation. This method also has not been entirely successful, for the reason that the establishment of any adequate partial vacuum in the car has the effect of sucking into the car through the numerous cracks and interstices of the car-frame a considerable quantity of warm air from the outside, with the result that if-a partial vacuum be maintained for even a very shorttime the temperature of the car is increased to a considerable extent, particularly so if the temperature of the outer air is high. Moreover, the dis lacement of the air in the fruit-packages and the coolin of it by the intermittent vacuum metho referred to is slow, incomplete, and wasteful, as a large amount of cold air is drawn from the car and exhausted into the atmosphere.

We have discovered, however,.that the objections experienced in the methods heretofore employed maybe avoidedand very satising ' the'upper portion of the car.

duced into the car in any suitable way, as by connecting the car with means for establishing a circulation of cold air therethrough. In carrying into efiect this principle we provide for intermittently introducin cold air into the car and causing it to circulate therethrough, the circulation of the air being stopped at intervals, so that the air in the car i through the car does not properly penetrate the fruit-packa es. During the "interval of rest, however, t e cold air in the upper portion of the car immediately falls, displacing the warm air in the lower portion of the car and in the fruit-packages, causin it to rise to y then restoring the circulation of cold air'through the car the warm air is carried out andcooled, the whole operation being accomplished without drawin atmospheric air into the car or wasting cold air by exhausting it into the atmosphere. Moreover, the air in the fruit-packages is practically all displaced by the colder air at each of the intervals of rest, so that the fruit itself is thoroughly cooled in a very short time.

In practice .we have found that very satisfactory results are secured by maintaining a full circulation of cold air for an interval of about thirty seconds, then maintaining a reduced circulation for about ten seconds, followed by an interval of rest for about ten seconds. After the interval of rest a reduced circulation is again maintained for ten seconds, preliminary to the next period of maintaining full circulation for thirty seconds. These intervals may; however, be varied, as the proper apportionment of the time and the rapidity of the flow of the air should. be varied according to the nature of the products to be transported. Some fruits require treatment for only a short time, while others require a longer time, and the same is true of vegetables, eggs, etc. Meats require treatmen t for a very much longer time than fruits, as they cannot be so quickly brought to the desired low temperature. i

So far as we are aware no one has heretofore contemplated securing the diffusion of cold air throughout a car or other receptacle containing perishable material by natural diffusion in connection with the establishment intermittently of a circulation of air as described. We therefore claim our im proved method broadly. It should be understood, moreoventhat while we have de scribed our improved method as applied to the cooling of air it is equally applicable in cases where the air is to be warmed and can 1 nected with the fruit-car, as will hereinafter also be ap lied in any other situation where it is desira le to equalize the temperature of a body of air the free circulation of a ortion of which is impeded to a greater or ess extent. It may also be employed toc ontrol the humidity or density of a confined body of air or gas, to regulate the precipitation of moisture or the separation of gases, or for any other purpose to which it is adapted.

The accompanying drawings illustrate forms of apparatus which may be employed in practicing our improved method; but such apparatus is not herein claimed, as it'will form the subject-matter of a separate application. 1

In said drawings, Figure 1 is an end view illustrating two cars, one of which is in section, showing one manner of carrying outour improved process. Fig. 2. is a detail of one of the connecting-conduits. Fig. 3 is a detail illustrating the clutch mechanism by which the fan is controlled. Fig. 4 is a partial longitudinal section of one form of work-car, and Fig. 5 is a side view of a fruit-car which may be used.

Referring to the drawings, 6 indicates the workcar,and 7 the fruit-car. The fruit-car may be one provided with ice-bunkers, as indicated by dotted lines at 8 in Fig. 5, or such bunkers may be omitted and other means provided for cooling the air which is caused to circulate through the car. Where the icebunkers are provided, other refrigerating mechanism is not necessary, and in that case the circulation of the air may be effected by the use of the mechanism hereinafter described or any other suitable mechanism without employing the refrigerating apparatus which has been illustrated. it will be understood, however, that for the purpose of making clear the manner in which we practice our method we have illustrated a romplete apparatus by which air at lhe proper temperature may be caused to rirrulate through the fruit-cars whether ice-bunkers are employed or not.

As illustrated in Figs. 1 and t, the workcar 6 is provided with a compartment S), which is adapted to contain a series of refrigerating-coils 10, suitably connected with a compressor ll in the manner common to refrigeraiing apparatus. The compartment 9 is preferably arranged between. the ends of the car and at one side thereof, so that the compressor 11 may be placed intermediately of the car at one side of said compartment, as shown in Fig. 4. 12 indicates an inlet-opening, which is arranged near the upper portion of the compartment 9, and 13 an outlet near the bottom of the opposite end of said coinpartment. The latter opening opens into duct or conduit 14, which communicates u an adjustable conduit 15 at the roof of the Said conduit 15 is adapted to be conappear. 17 indicates a condenser, which is preferably placed on the roof of the car and is connected with the coil in the usual way. 18 indicates a conduit which communicates with the inletopening 12. provided with a fan-chamber 19, in which a blower of any suitable construction is placed for causing the air to circulate through the various conduits, chambers, and fruitcars. The fan is illustrated at 20 in Fig. 1 and is mounted on a shaft 21, suitably supported, preferably by hangers 22.v It is driven in any suitable way, as by an engine 23, which drives the shaft 21 through a belt 24 .or by any other suitable means. The belt 2.4 runs over a pulley 25, which is loosely mounted on the shaft 21 and is adapted to be connected thereto by a friction-clutch 26 or any other suitable means for transmitting powerto the shaft 21 and permitting variation in speed of said shaft, so that the fan maybe slowed down or stopped, as desired. Where the clutch 26 is em loyed, it may be operated by a lever 27, asi lustrated in Fig. 3. 28 indicates a boiler for supplying steam to the en gine 23.

As shown in Fig. 1, the conduit 18 communicates through the roof of the car with a conduit 29, which is adapted to-be swunginto and out of operative connection with a fruitcar placed on a parallel track, as shown. Said conduit has a bearing in the roof of the work-car, as shown at 30 in Fig. 2, so that it may be swung toward and fromthe fruit-car an may also be raised and lowered, so as to move into and out of operative connection with the fruit-car, the projecting portion 30 of the conduits being telescoped in its bearing, as shown in Fig. 2. The conduit 15 at the opposite end of the caris similar to conduit 29. In order to rovide a tight connection between the con uits 29 and 15 and the fruit-car and compensate for the slope of the conduits 29 and 15 are provided with flanges 32, which rest onsaid pads when the conduits are in position, as shown, thus providing substantially tight connections. I The apparatus is operated as hereinbefore described, the fan being slowed down or stopped, as necessary, by operating the lever 27. Where thefruit-cars are provided with the ice-bunkers, the course of the air is not altered, but the compressor is not operated. The compressor may receive steam from the boiler 28 or may be operated in any other suitable way.

We wish it to be understood that any suit able apparatus for the purpose may be employed in practicing ourimproved method, also that althou h we have described our process as app'lie to railway-cars it may be Said conduit is applied to any other suitable chamber or resire to secure by Letters Patent, is-

1. The method of regulating the temperature of air in a chamber, which consists in displacing by convection a art of the air in said chamber with an intro uced thereinto at a difierent temperature, and then directing a current of air through said chamber.

2. The method of regulating the temperature of air ina chamber, which consists in directihg a current of air at a different temperature through said chamber at intervals, and permitting the air therein to diffuse by convection.

3. The method of regulating-thev temperature of air in a chamber, which consists in introducing cool air into said chamber, permitting the air so introduced to diffuse therein by convection, and then causing a circulation of air through'said chamber.

4. The method of regulating the temperature of air in a chamber, which consists in establishing a circulation of cool air through said chamber,permitting the air so introduced to difiuse therein by convection, and then again establishing a circulation of cool air through said chamber.

5. The method of regulating the tempera ture of air in a chamber, which consists in introducing into said chamber air at a temperature different from that in said chamber permittingit to diffuse therein by convection and then causing a circulation. of air through said chamber.

6. The method of regulating the condition 'of air in a chamber, which consists in displacing by convection a part of the air in said chamber with air of different density intro-- duced thereinto and then directing of air through said chamber.

7. The method of regulating the condition of air in a chamber, which. consists in alter-. nately introducing air into said chamber and permitting it to difiuse therein by convection the air introduced being of a'diiferent density from the air contained in said chamber.

8. The method of regulating the condition of air in a chamber, which consists in displacing by convection a part of the air in said a current chamber with air of different humidity introduced thereinto and then directing a current of air through said chamber.

9. The method of're ulating the condition of air in achamber, w ich consists in alternately introducing air into said chamber and permitting it to iffuse therein by convection, the air introduced bein of a different humidity from the air containe in said chamber.

PAUL MANDEVILLE. WILLIAM C. WALKER. Witnesses:

' JoHN ,L. JACKSON,

WILLIAM H. DE BUsK- 

